Abstract: In a no-charge-exchange transfer, the transfer sheet leaving a no-charge-exchange transfer roller contains little or no electrical charge except for the charged toner. Accordingly, the charged toner tends to explode off the sheet or migrate on the sheet due to like charge on the toner causing toner particles to repel each other. A neutralizing corona is provided adjacent the image side of the copy sheet. This corona is positioned after the nip of the transfer roller and before the copy sheet leaves the transfer roller. Ions emitted from the neutralizing corona reduce the charge on the toner particles to substantially zero. Thus, the toner particles no longer repel. Forces of adhesion hold the particles to the paper after the sheet leaves the transfer roller and proceeds to the fusing station.

Abstract: Airborne electrophotographic toner particles are filtered by a body of carrier beads of a material selected to develop a relatively high triboelectric charge upon contact by the toner particles. When the filtering capability of the body of carrier beads is exhausted, the carrier beads and the collected toner are simply mixed into the developer mix of a xerographic machine whereby the collected toner can be reused.